1. MacCallum, M. A. H., and Taub, A. H. (1973).Commun. Math. Phys. 30, 153.
2. Piotrkowska, K., and Zalaletdinov, R. M. (1995). InInhomogeneous Cosmological Models, A. Molina, and J. M. M. Senovilla, eds. (World Scientific, Singapore), p.97.
3. Misner, C. W., Thorne, K. S., and Wheeler, J. A. (1973).Gravitation (W. H. Freeman, San Francisco).
4. Thorne, K.S. (1987). In300 Years of Gravitation, S. W. Hawking and W. Israel, eds. (Cambridge University Press, Cambridge), p.330.
5. Brill, D. R., and Hartle, J. B. (1964).Phys. Rev. 135, B271.